[Android] Add a configurable environment for devil/.

build/android/test_runner.py

Index: build/android/test_runner.py
diff --git a/build/android/test_runner.py b/build/android/test_runner.py
index db6df24b321e062df5746893c698b76bf7cdbfeb..a41478cea5412617f6b1f71cab4ec3f59279ee60 100755
--- a/build/android/test_runner.py
+++ b/build/android/test_runner.py
@@ -17,6 +17,7 @@ import threading
 import unittest
 
 from devil import base_error
+from devil import devil_env
 from devil.android import apk_helper
 from devil.android import device_blacklist
 from devil.android import device_errors
@@ -49,6 +50,10 @@ from pylib.uiautomator import setup as uiautomator_setup
 from pylib.uiautomator import test_options as uiautomator_test_options
 
 
+_DEVIL_STATIC_CONFIG_FILE = os.path.abspath(os.path.join(
+    constants.DIR_SOURCE_ROOT, 'build', 'android', 'devil_config.json'))
+
+
 def AddCommonOptions(parser):
   """Adds all common options to |parser|."""
 
@@ -113,6 +118,22 @@ def ProcessCommonOptions(args):
     constants.SetOutputDirectory(args.output_directory)
   if args.adb_path:
     constants.SetAdbPath(args.adb_path)
+
+  output_binary = lambda p: os.path.join(args.output_directory, p)
+  devil_dynamic_deps = {
+    'md5sum_host': [output_binary('md5sum_bin_host')],
+    'md5sum_device': [output_binary('md5sum_dist')],
+    'forwarder_host': [output_binary('host_forwarder')],
+    'forwarder_device': [output_binary('forwarder_dist')],
+  }
+  if args.adb_path:
+    devil_dynamic_deps['adb_path'] = [args.adb_path]
+
+  devil_dynamic_config = devil_env.GenerateDynamicConfig(devil_dynamic_deps)

[jbudorick, 2015/09/29 13:28:57]

As written, the dynamic config takes precedence over the static config, so a
user with out/Debug/... and custom_output_dir/Debug/... that passes
--output-directory=custom_output_dir/Debug will correctly use the binaries from
custom_output_dir/Debug/...

+  devil_env.config.Initialize(
+      configs=[devil_dynamic_config],
+      config_files=[_DEVIL_STATIC_CONFIG_FILE])
+
   # Some things such as Forwarder require ADB to be in the environment path.
   adb_dir = os.path.dirname(constants.GetAdbPath())
   if adb_dir and adb_dir not in os.environ['PATH'].split(os.pathsep):